Medication Assisted Treatments

A variety of treatment approaches

Medication Assisted Treatments (MAT):“The use of FDA-approved medications in combination with evidence based behavioral therapies to provide a while-patient approach to treating substance use disorders (SUDs). “ CMS bulletin in MAT.

Benefits of MAT

Also lowering risk of HIV or Hep C

Three Major Strategies

Agonist or Substitution Therapy: Examples-methadone or nicotine patch.

01Antagonist Therapy: Example-naltrexone.

02Punishment Therapy: Example-Antabuse.

03

Alcohol

• Acute Alcohol Withdrawal Syndrome: tremors, tachycardia, hypertension, perfuse sweating, insomnia, hallucinations and seizures.• Often requires inpatient medical management.

• Two goals of acute detoxification:• Reduce autonomic hyperactivity• Prevent development of seizures

Alcohol-Benzodiazepines and acute EtOHwithdrawal

• High cross-tolerance between alcohol and benzodiazepines.• Benzodiazepines have a longer t½ than EtOH, and withdrawal can be

done safely.• The neuroinhibitory actions of benzodiazepines potentiate the action

of GABA which significantly decreases the risk of seizures.• Increased autonomic arousal or stress response which comes with

EtOH withdrawal is diminished with increased GABAergic transmission.• Rapid acting benzos are problematic (such as alprazolam) due to

abuse potential.

The FDA approved drugs for EtOH abuse and dependence. • Disulfiram (Antabuse®)• Natrexone (Vivitrol®-tablet, Revia®-IM injection)• Acamprosate (calcium acetylhomotaurinate or Campral®)• All used for Maintenance treatment• Typically used for weeks or months• Indefinite maintenance is unusual.

Disulfiram (Antabuse®)

• Unpleasant reaction• Flushing, accelerated pulse, throbbing

headache, nausea and vomiting• Increased acetaldehyde in the body due to

inhibition of aldehyde dehydrogenase by disulfiram.

• Not shown to be effective in achieving abstinence or delaying relapse.• Most individuals simply do not take the

medication.

Naltrexone (Vivtrol®, Revia®)

• Initially developed for opioid dependence.• Found to reduce the days of EtOH

drinking per week, reduced rate of relapse, reduced craving.• Thought that the blockade of opioid

receptors, prevents the release of opioid induced dopamine release, which in turn blocks reinforcing effects of EtOH.

Acomprosate (Campral®)• Action:

• normalization of basal GABA concentrations, which are disrupted in EtOH dependent individuals.

• Blocks glutamine increases observed during withdrawal.

• Mechanism of Action: bears structural resemblance to GABA. Opens the chloride ion channel in a novel way as it does not require GABA as a cofactor, making it less liable for dependence than benzodiazepines.

• Half Life: 20-33 hours• Kidney excreted

• Contraindicated in severe kidney failure (renal failure), and dose reduction necessary for those with impaired kidneys.

Nicotine• Withdrawal symptoms include: anxiety, depression, dysphoria, irritability, decreased

concentration, insomnia, increased food intake and cigarette (nicotine) craving.• Pharmacotherapies have been used primarily to attenuate withdrawal symptoms.

• Nicotine replacement therapies• Bupropion (Zyban®)• Varenicline (Chantix®)

Nicotine Replacement Therapies

• Five FDA approved products:• Transdermal Patch• Nicotine Gum• Nicotine Nasal Pray• Nicotine Vapor Inhaler• Nicotine Lozenge

• Must not use other nicotine containing products at the same time.• Concerns about nicotine toxicity

Bupropion (Zyban®)

• First non-nicotine pharmacotherapy for smoking cessation.• Inhibition of dopamine and nor-

epinephrine reuptake.• Blockade of acetylcholine receptors.• No absolute requirement for user to

abstain from nicotine containing product use. • Theoretically should be beneficial together

with nicotine replacement but studies show no advantage of bupropion addition to nicotine replacement treatment.

Varenicline (Chantix®)

• Approved smoking cessation medication.• A partial nicotinic-receptor agonist.• Even at large doses, it doesn’t

produce the full response of nicotine.

• Reduce withdrawal and cravings.• Found to be more effective than

placebo or bupropion.

Stack, N.M. “Smoking Cessation: An Overview of Treatment Options with a Focus on Varenicline”. Pharmacotherapy 27 (2007), 1550-57.

Called Champix in

Canada.

Opioids- approach to withdrawal

Historically: belladonna was used (strong anticholinergic drugs) to produce delirium, lasting for several days, at which time the dependent person would emerge cured of dependence without remembering dreadful withdrawal.

Newer: “Rapid opioid detoxification”, where dependent patients are anesthetized, given opioid antagonists when unconscious, so withdrawal occurs while unconscious. After 24 hours, patient released to counseling and continued opioid antagonist treatment.

Lofexidine Hydrochloride (Lucemyra®)

• Frist non-opioid drug to help treat symptoms of opioid withdrawal in adults• Ease symptoms of diarrhea, nausea, vomiting, anxiety and overall feeling of

sickness• Alpha 2 receptor agonist

• Reduce the release of norepinephrine

• Side Effects: hypotension, brady cardia, somnolence, sedation, dizziness.• A few cases of syncope (fainting)• Lower blood pressure, risk of abnormal heart rhythms

• After time not using opioids, patients may become more sensitive

FDA Approved Opioid Dependence Treatments• Methadone: long duration of action, developed in WW2 Germany as an

analgesic. Reduces cravings by activating opioid receptors in the brain. CII.• Buprenorphine: partial opioid agonist, with a large margin of safety, and low

overdose potential. Reduces or eliminates opioid withdrawal symptoms, including cravings without producing the euphoria or dangerous side effects of opioids such as heroin. Low abuse potential, high availability for office use. High cost and possibly not effective for patients requiring high methadone doses. CIII.• Naltrexone: long acting opioid antagonist for treating opioid dependence.

Naltrexone is used for preventing relapse in adults following complete detoxification from opioids. • Naloxone is a short acting opioid antagonist with greater affinity for brain opioid receptors

than most opioid agonists, including heroin. Used for treating opioid overdose. Quickly reverses or blocks effects of other opioids, restores normal respiration.

• Buprenorphine/Naloxone: opioid agonist and antagonist. Not recommended for use during induction for long acting opioids or methadone. CIII.

With minimum 8 hours of training for providers. The Drug Addition Treatment Act of 2000 enabled physicians to provide office

based treatment for opioid addiction.

Buprenorphine-partial agonistNaloxone-antagonist

• Buprenorphine is a partial agonist, thus receptor activation increases as the dose increase until it reaches a PLATEAU.• When displacing other opioids, it can cause

withdrawal symptoms.• Withdrawal less severe after discontinuation.

• Full opioid agonists, such as methadone and heroin, continue to create increased receptor activation as dose increase, never reaching a plateau.

• Antagonists will not produce receptor activation regardless of dosing.

Subutex=buprenorphineSuboxone=buprenorphine and naltrexoneIV-precipitates abrupt withdrawalSL- naloxone barely bioavailable so very low dose reaching blood.

Methadone• Indications

• Detoxification of opioid dependence• Pain management, for which alternative treatment options are inadequate.

• Initial dosage:• 20 to 30 mg (as a single dose) when there are no signs of sedation or intoxication and

patients shows symptoms of withdrawal. • Lower doses should be considered in patients with low tolerance at initiation (eg, absence of

opioids for at least 5 days); • an additional 5 to 10 mg may be provided if withdrawal symptoms have not been suppressed

or if symptoms reappear after 2 to 4 hours; total daily dose on the first day should not exceed 40 mg.

• Dose adjustment: Do not increase dose without waiting for steady-state to be achieved. Levels will accumulate over the first few days; deaths have occurred in early treatment due to cumulative effects.• Maintenance dosage:

• 80 to 120 mg/day (titration should occur cautiously). • Titrate to a dosage which prevents opioid withdrawal symptoms for 24 hours, prevents

craving, attenuates euphoric effect of self-administered opioids, and tolerance to sedative effects of methadone.

Buprenorphine Dosage Forms (CIII)• Belbuca ®

• Buccal Film is mainly for pain management. Breakthrough pain for those on round the clock, long term opioid treatment.

• Peak effect 2.5-3 hrs.• Buprenex ®

• IM and IV injection for quick onset with one hour peak effect and 6 hour duration of action.• Generic Buprenorphine HCl

• Sublingual tablet and injection.• SL tablet time to peak is 30 minutes to 1 hour.• SL tablet used for opioid dependence treatment (vs film for breakthrough pain)

• Butrans ®• Weekly patch, used for pain requiring round the clock long term opioid treatment.• Time to peak is approximately 3 days

• Probuphine®• Implantable buprenorphine for opioid dependence for those stabile on low to moderate

doses of trans mucosal product for 3 months or longer.• Insertion• Med-Guide

Naltrexone (Revia®, Vivtrol®)

• Opioid antagonist with highest affinity for mu receptor.

• Has little or no opioid agonist activity. • Naltrexone blocks the effects of opioids by

competitively binding opioid receptors. • This makes blockade potentially

surmountable with opioid use, which can cause other non-opioid receptor mediated symptoms such as histamine release.

Naltrexone-Warnings

• Contraindicated in persons who fail to pass naloxone challenge or positive urine screen for opioids.• Especially when using naloxone for EtOH treatment (can

overlook concurrent, undisclosed, opioid use)• Must be opioid free for minimum of 7-10 days for patients

previously dependent on short acting opioids. • Must be opioid free (including tramadol) before starting to

use naltrexone. • There is no completely reliable way to determine if patient

has had adequate opioid free period (even if urine tox. screen looks OK). • Be prepared to manage withdrawal symptomatically

always.

• Patients on naltrexone involved in an accident and requiring pain relief pose a special challenge.• Non-opioid pain management • Local pain blockade• High dose hydromorphone (Dilaudid®) is used with

extreme caution (and only in hospital)

Naltrexone-Warnings

• Patients at end of dosing interval, discontinued treatment, or missed dose• Have very sensitive opioid receptors• Dangerous if exposed to even small doses• Dangerous if exposed to high doses as used before treatment (or using

during treatment and naltrexone dose wears off)

• Naltrexone blocks the effects of exogenous opioids for approximately 28 days after administration.

• Discontinue extended release IM naltrexone at least 30 days prior to surgery.

Buprenorphine-Natrexone (Suboxone®)®®

Cocaine Detoxification Treatment

• Withdrawal doesn’t seem to be a major feature of cocaine dependence.• Some documented symptoms:• Depression• Nervousness• Dysphoria• Anhedonia• Fatigue• Irritability• Sleep and activity disturbances• Craving for cocaine

Modafinil (Provigil®) for cocaine withdrawal treatment.

• Modafinil is known to bind to dopamine transporter (DAT).

• Increased synaptic DA leads to increased tonic firing and downstream release of neurotransmitters involving wakefulness: orexin and histamine.

CannabisMost consume infrequently, small proportion of users become dependent (1:11)

Withdrawal characteristics:irritabilityanxietysleep disruptionaches

The only effective treatment studied thus far: dronabinol (oral THC or Marinol®)Substitution of a longer acting pharmacologically equivalent drug.

https://store.samhsa.gov/apps/matx

End MAT

• Thank You!